How to pack food for Marathon

The feeling of a long run is primal and transcendent, but so is that all-consuming, knee-trembling feeling of hunger and nausea that makes you desperate for food—while also questioning your ability to keep it down.

This is the challenge of the mid-workout meal: It needs to be full of energy and easy to digest. In fact, in the middle of a long run, many conventional dietary rules go out the window. Rather than protein and healthy fats, the body needs fast-absorbing carbohydrates—food that will spike insulin and send sugars rushing through the bloodstream to fuel the muscles that need them . “It’s even a good idea to avoid more fibrous food, like sweet potatoes,” says Greatist expert Jason Fitzgerald. “The fiber can exacerbate stomach cramps.”

Mid-run snacking isn’t really necessary unless you’re exercising for more than hour. But if that’s the case, it’s good to start eating between 30 and 60 minutes in, at the rate of about 30 to 60 grams of carbohydrates per hour. Here’s what you need to know.